The present invention relates generally to the fields of telecommunications and penal institution management. More particularly, the invention relates to a computer-based method and apparatus for controlling, monitoring, recording and reporting access to outside telephone lines in a controlled, institutional environment, such as a prison, military base, hospital, school, business or government organization. Specifically, this invention relates to apparatus for detecting when a called party has proceeded to bridge together one telephone call with another telephone call, through the detection of dial tones, dual tone multi-frequency (DTMF) tones, special information tones (SIT), ring signals, busy signals, dial tones, other call progress tones, or similar tone signals, without the necessity of sensing or detecting hook switch or flash signals, which may be problematic.
Generally, the need to control access to outside telephone lines in an institutional environment is well recognized. In order to prevent individuals from incurring large, unaccountable telephone costs which the institution ultimately bears, one must either restrict access to outside telephone lines or institute accounting controls whereby the costs of unauthorized calls can be billed to the responsible individuals.
Telephone systems in correctional environments require additional security considerations. Without appropriate controls on telephone access, inmates have been known to use the telephones to harass outside parties (such as witnesses who testified against them, attorneys who prosecuted their case, employees of the courts, etc.), to perpetrate fraudulent schemes, and to participate in criminal conspiracies (such as arranging the smuggling of contraband into the prison, directing an outside criminal enterprise, plotting escape attempts or credit card fraud). Therefore, it is critically important for correctional management officials to carefully plan, control, monitor and record inmate access to outside telephone lines.
One of the most fundamental problemsxe2x80x94which exists both in correctional and other business-oriented institutionsxe2x80x94is cost control. To achieve cost control, it is critical that there be individual accountability for each call that incurs a charge to the institution. Such accountability is typically achieved through use of personal identification numbers (xe2x80x9cpinsxe2x80x9d). Before making a call from an institution telephone, an individual must enter his PIN. The telephone service provider is then able to deliver to the institution an end-of-the-month telephone bill which lists, in addition to the cost of each call, the PIN or name of the individual who made the call. From this information, the institution can then collect reimbursement from individuals for the costs of certain calls.
While this system of end-of-the-month call accounting functions reasonably effectively in a business like environment, it does not work well in a penal institution. The reason is that inmates show little concern for phone bills they can""t afford to pay. Thus, the institution is often forced to absorb the costs of phone calls by its delinquent inmates. Moreover, the fact that account balances are only computed periodicallyxe2x80x94i.e., every month, week, or even every dayxe2x80x94permits the inmate to accrue large, uncollectible phone bills before his access to the phones can be terminated. Traditionally, penal institutions have addressed this problem by restricting inmates to collect calls only. This, however, still provides the inmates with relatively unlimited access to the outside world, leaving open numerous opportunities for fraudulent and criminal activity, as explained below. Therefore, in a penal environment, it is highly desirable to regulate phone access on an individual, pay-in-advance basis, and to immediately and automatically terminate an individual""s phone access when his/her paid-up account reaches a zero balance.
Another problem in penal institutions is the inmates"" desire to make threatening or harassing phone calls to witnesses, prosecutors, police officers, parol officers, psychologists, judges, and the relatives and family of such persons. Limiting the inmates"" access to collect calls only, does not effectively address this problem, since an inmate can easily identify himself (to an operator) as someone from whom the recipient would likely accept a collect call. Rather, one should, at a minimum, provide a means that permits a potential call recipient to identify the caller as an inmate before accepting the call, whether that call is placed on a prepaid or collect basis. Conventionally, this is done by initially placing the inmate on hold and playing a pre-recorded message telling the recipient that a call has been placed from a correctional facility and that, if the recipient wishes not to receive the call, he/she should hang up before the call is connected. This approach mitigates, but does not fully solve, the harassment problem. In particular, it is still possible for an inmate to repetitively call an outside party; even if the recipient hangs up after hearing the pre-recorded message, the harassing effect of receiving repetitive calls from inside the correctional institution remains. Therefore, it would be highly desirable to provide an institutional telephone system that automatically prohibits inmates from attempting to call certain outside persons. Moreover, it would also be highly desirable to provide a method and apparatus for allowing a recipient of an undesired call from an inmate to easily and automatically prohibit all future calls from that particular inmate, or from all inmates generally.
Still another concern in correctional institutions is the regulation of access to telephone systems. For various security and management reasons, it often desirable to restrict a given inmate""s telephone access to particular phones, calling times, and to limit the length of calls, number of calls, and number of calls to the same number. Also, to enhance security and discipline, it should be possible to instantaneously revoke an inmate""s calling privileges, or to otherwise modify the extent of a particular inmate""s calling privileges.
Correctional institutions also typically wish to monitor and/or record outgoing calls. Inmate-to-attorney calls, however, cannot legally be monitored or recorded. Moreover, certain inmatesxe2x80x94those who represent particular security risksxe2x80x94deserve live monitoring, as opposed to mere recording. Thus, it would be highly desirable to have a system which automatically initiates the appropriate monitoring and/or recording depending upon the identity of the inmate placing a call and the recipient of the call (i.e., attorney or non-attorney). Likewise, it may be desirable that calls to certain numbers are to be monitored live, while others need only be recorded.
Because the message content of inmate-to-attorney calls cannot be legally recorded or monitored, such calls can serve as a conduit for the inmate""s illegal telephone activity. Therefore, it would be highly desirable to have a system which could passivelyxe2x80x94that is, without in any way monitoring or recording what is actually being saidxe2x80x94monitor inmate-to-attorney calls to ensure that: (1) the only two people speaking on the line are the inmate and attorney, and/or (2) no DTMF tones, rapid line impedance changes, off-hook conditions or voltage spikes appear on the line. Techniques for voice identification are knownxe2x80x94i.e. U.S. Pat. Nos. 4,993,068, entitled UNFORGEABLE PERSONAL IDENTIFICATION SYSTEM and 5,150,357, entitled INTEGRATED COMMUNICATIONS SYSTEM, both incorporated herein by referencexe2x80x94but have not been previously used in penal telecommunications applications.
One patent, U.S. Pat. No. 4,726,057 to Doerry et al. explained many of the problems brought about by the deregulation of the telephone industry in the United States. That patent states: xe2x80x9cPrior to a June, 1984 FCC decision, pay telephones were the exclusive province of the various Telephone Companies while others were precluded from the business of providing pay telephone service. Today, however, subject to state Public Utility Commission regulations, Customer Owned Coin Telephone (COCOT) service is permitted, but a number of non-trivial technical challenges have been created including called party answer detection.
Coin telephones (pay phones) owned by the local Telephone Company generally utilize DC signals to signal called party answer. Such information is specially communicated between telephone central offices and then to the originating pay phone telling it when to accept the deposited coins. Such information, however, is not communicated to conventional telephones and it is only with great difficulty that called party answer can be detected. Naturally, the calling party knows when a connection is completed; but a knowledge of human frailty suggests that he not be relied upon to turn the xe2x80x9cmeterxe2x80x9d on.
Complicating the problem of answer detection is the existence of special information messages that are provided when, for example, a telephone has been disconnected or a new telephone number has been assigned; and while certain tones are indicative of a proper answer, other tones are not. Ringing, busy and reorder signals as well as background noise and feedback from the calling party herself (sidetone) make answer detection a formidable challenge.xe2x80x9d
The problems set forth above are exacerbated by the fact that callers, such as inmates in a prison, have the ability to work in concert with others outside of the facility. For example, an inmate may be restricted from calling a particular judge who sentenced him, however, that inmate may call his spouse, who in turn may set up a conference call to the judge, thus allowing the inmate to verbally abuse the judge. Such a conference call may be prohibited by law, however, the correctional facility cannot prevent it, as the called party, in this case, the spouse, has the ability to bridge callers with other outside, unrestricted telephone lines, thus giving the inmate unrestricted telephone access.
Present attempts to solve the problem of called party bridging, or so-called third party calls, have shortcomings. For example, one attempt at resolving this problem is disclosed in U.S. Pat. No. 5,319,702, to Kitchin et al. In that patent, the need to provide an apparatus for use in conjunction with so-called xe2x80x9clocal equipment/telephone.xe2x80x9d When the local equipment/telephone is in telecommunication with a remote telephone, (i.e., when a telephone call is established therebetween), the apparatus is capable of indicating whether the remote party has performed a specific act causing the generation of a hook flash-type signal which is detected by the apparatus. In that patent, the detection of a hook flash-type signal is presumed to solve the problem of unauthorized calls to third parties, such as a telephone call from an inmate to the judge who sentenced him, as set forth above. The apparatus of that patent includes a band filter for passing energy having certain frequencies and an energy detector for detecting a specific electrical energy pulse having been filtered by, i.e. passed through the filter, and having a predetermined minimum magnitude. The apparatus of that patent further describes in part software (referred to as window analyzation means) which cooperates with the energy detector to detect a specific event(s) occurring on the telephone line during a predetermined maximum time window following the detection of a specific pulse on the telephone line, i.e., when a telephone call is in progress between the local party/equipment and the remote party. The detection of a specific event(s) on the line provides an indication as to whether the remote party has performed a specific act such as (1) attempting to initiate a 3-way conference call, (2) accepting a call or the charges therefor, (3) terminating a call before the local equipment/party terminates the call, and (4) dialing a specific number on a remote rotary/pulse telephone. Further, the apparatus of that patent is said to be suitable for use in a computer controlled telephone wherein the energy detector detects when a called party has answered a call initiated by the computer operated telephone and dialed a pulse/dial telephone or activated (flashed) the hookswitch. The energy detector is said to do this by measuring incoming electrical signal energy in a particular frequency band. Then, according to that patent, the software window analyzer cooperates with the energy detector to provide efficient and reliable protection of a called party""s pulse dialing of a digit (usually a xe2x80x9czeroxe2x80x9d) to verify the called party""s acceptance of a call or a collect call or the called party""s attempt to activate 3-way calling by flashing the called party""s telephone hookswitch.
The energy detector of U.S. Pat. No. 5,319,702 to Kitchin et al. is also said to include an absolute value level detector circuit that determines when an energy pulse having passed through the band filter is above a predetermined level. If above a predetermined level, the information is transmitted by the energy detector to the apparatus"" controlling computer. As previously mentioned, the apparatus further includes software, i.e., the aforementioned window analyzer, for cooperating with the energy detector to detect specific event(s) occurring on the telephone line during a predetermined maximum time window following a detection of the specific pulse. In the situation where the apparatus according to that patent is said to be designed or programmed to detect a remote party""s attempt to initiate a 3-way conference call, the software window analyzer is said to include a timer or timer means for cooperating with the energy detector so that the timer begins running for a first predetermined period when a specific energy pulse is detected by the energy detector. The software window analyzer also includes sound detection means for detecting sound on a telephone line and for cooperating with the timer so that the sound detection means is activated at the end of the first predetermined period for a second predetermined maximum time period. If sound is not detected during the second predetermined time period, such indicates that the remote party has attempted to initiate a 3-way conference call.
Kitchin discloses a type of energy detector that can also incorporate a ringback detectorxe2x80x94not to activate third party call blocking, but merely for activating the energy detector when the ringback signal is detected. Thus, the ringback detector is used to set the energy detector, so that the energy detector can purportedly carry out the purpose of that patent, and so that the energy detector can be utilized. Indeed, Kitchin states that xe2x80x9c[t] hose skilled in the art will appreciate that called party answer is indicated when the first specific energy pulse is detected after the apparatus has detected the called party""s ringback signal.xe2x80x9d Thus, the ringback signal is used to initialize the Kitchin systemxe2x80x94not to solve the problem at hand. In that sense, Kitchin teaches away from relying upon the use of ringback detection as a means to block third party calls.
The Kitchin patent discloses xe2x80x9cbeing useful for detecting certain specific events, i.e., call answer, an attempt to initiate a 3-way conference call, call acceptance, call termination, and determining the specific number dialed number on a rotary/pulse telephone. Any event which causes the generation of the hook flash-type signal such as a call waiting signal can purportedly be detected. Importantly, Kitchin says that it can detect xe2x80x9cany event which causes the generation of the hook flash-type signalxe2x80x9d. This is important because that is the entire focus of the Kitchin patentxe2x80x94to detect hook flashes, or the energy pulses associated therewith. This approach is problematic, as it relies on the detection of a pulsexe2x80x94not the detection of certain tones. While the Kitchin patent may appear to be an elegant solution to the problem of blocking third party calls, it is needlessly complex, and if anything, complicates the process of detecting the attempted establishment of third party calls. The prior art does not teach the simple, direct method of sensing third party call patterns by merely monitoring the occurrence of tones that called parties traditionally generate in their efforts to bridge callers with third parties. In essence, many called parties allow the caller to be on the line while they dial the third partyxe2x80x94that is an opportunity to sense DTMF tones. Then, many called parties may dial the wrong number of the third party, and a SIT tone will indicate that number may have been disconnected, subject to an area code change, or the likexe2x80x94all while the caller is on the line. That is another opportunity for sensing tones to prevent third party calls. Also, called parties may use a credit card to call third partiesxe2x80x94also while the caller is on the line. Call progress tones may be generated during such credit card callsxe2x80x94thus, yet another opportunity to sense tones to prevent third party calls. Also, if at any time during the call, a ring or busy signal is heard on the caller""s telephone, still another opportunity is present for sensing tones to prevent third party calls. And finally, if at any time during the call while the inmate is on the line, a dial tone occurs (as when a called party may go off-hook to place the call to the third party), yet another opportunity exists for sensing tones to prevent third party calls.
In light of the above, one object of the invention is a method of managing telephone activity in an institutional environment to achieve improved security and reduced cost. Another object of the invention is a system adapted to perform such improved institutional telephone management.
Yet another object of the invention is a method and apparatus for passively monitoring a telephone connection to detect security breaches.
A still further object of the invention is an institutional telephone management system wherein the parameters that control the operation of the system as well as the records of system activity are stored in a central database, thereby permitting simple customization of system operation, generation of reports and monitoring of status.
In accordance with one aspect of the invention, a method of managing telephone activity in an institution includes the steps of: (1) identifying an institutional caller (the xe2x80x9ccalling partyxe2x80x9d) who wishes to place an outside call to an outside recipient (the xe2x80x9ccalled partyxe2x80x9d); (2) blocking the institutional caller and xe2x80x94while the institutional caller""s line (earpiece and/or mouthpiece) remains blockedxe2x80x94(a) calling said outside recipient (called party), (b) providing the identity of said institutional caller to said outside recipient and (copyright) receiving a control code from said outside recipient; (3) determining, in response to said control code, whether to connect the institutional caller to the outside recipient, and optionally, whether to indicate any of a plurality of messages to the calling party, e.g., an inmate, and (4) terminating or otherwise tracking or accounting for calls to third parties whereby attempts are made by the called party to bridge or conference the calling party (the caller or inmate) with any third party.
In accordance with another aspect of the invention, an apparatus for managing telephone activity in an institution includes: a plurality of institutional telephones located within the institution; a trunk management unit (TMU) for selectively connecting the institutional telephones to one or more outside telephone lines, wherein the TMU includes means for decoding DTMF tones generated by the institutional telephones or received from the outside telephone lines; and a computer control unit (CCU), coupled to the TMU, for controlling the connection of the institutional telephones to the outside telephone lines based upon DTMF tone(s) received from the outside telephone lines. A database associated with the CCU contains information regarding the calling privileges of each person within the institution. In a preferred embodiment, the TMUxe2x80x94prior to connecting the callxe2x80x94plays an announcement to the called party identifying the institution and caller, along with the options available to the called party. In response, the called party may enter the announced DTMF tone sequence (preferably GOTU), which modifies a record in the database, thereby prohibiting the caller (and/or other similarly situated prospective callers) from calling the called party in the future.
Other features of the TMU provide security and monitoring functions. The invention provides three levels of monitoring, any or all of which may be active for any given call. The first level is xe2x80x9clivexe2x80x9d call (voice) monitoring, where the prison officials actively listen to a live call. The second level is call recording. The TMU can be programmed to enable associated recording equipment to record telephone calls. The third level is xe2x80x9cpassivexe2x80x9d line monitoring, where the TMU detects, for example, DTMF tones, off-hook conditions, voltage spikes and/or sudden line impedance changes, in order to thwart attempts at unauthorized three-way calling, call conferencing, call transferring, call forwarding or re-dialing via various alternate common carriers, many of whom now offer xe2x80x9c1-800xe2x80x9d or local telephone number (e.g., xe2x80x9c950xe2x80x9d) access numbers. Also, care is taken to avoid disrupting calls that do not represent security breaches, by preventing false triggering of the above xe2x80x9cpassivexe2x80x9d line monitoring features. For example, with respect to DTMF tone blocking, the TMU will look for any additional digits entered by an institutional caller, such as an inmate, to prevent the inmate from redialing to other telephone numbers that may not be authorized. However, to prevent xe2x80x9ctalkoffxe2x80x9d, whereby the normal telephone conversation can falsely trigger a disconnect signal (because the TMU may interpret the conversation as DTMF dialing), the TMU can be set to look at the number of digits dialed within a specified time period (e.g., six (6) digits within a fifteen (15) second time period, or any variation of the two parameters) and thereby, determine whether the audio information is indicative of unauthorized DTMF redialing or just a normal speech or voice pattern.
In accordance with the preferred embodiment of the invention, all calls are passively monitored and all calls that can be legally recordedxe2x80x94i.e., all but inmate-to-attorney callsxe2x80x94are recorded. At any time, prison officials can selectively invoke live monitoring to listen in on any call in progress, except an inmate-to-attorney call. System alarms, which trigger any time a particular inmate places a call or calls a certain person, allow officials to determine when live call monitoring is appropriate. Likewise, the telephone system of the present invention can be programmed to default in any manner. For example, the system can be set to place only those telephone calls that are among a pre-approved list of telephone numbers. Conversely, the system can be set to place all telephone calls except those that are among a list of restricted telephone numbers. Optionally, the telephone system of the present invention can include speed-dialing, whereby upon entering a PIN, for example, an inmate can enter xe2x80x9c11xe2x80x9d followed by the xe2x80x9c#xe2x80x9d key. In that case, the prison administrator may have established that xe2x80x9c11xe2x80x9d is the speed-dialing sequence for that inmate""s mother. Of course, the system could be configured so that the inmates themselves can program the telephone system with speed-dialing digits, however, a principal objective of speed-dialing is to save time at the telephone, thus making the telephones available to the largest number of inmates in the shortest possible time period.
In addition, the invention may include biometric voice verification features. The TMU, for example, may digitize a sample of the caller""s voice. The CCU then compares the digitized sample with a stored voice print, to verify the identity of the caller. Such biometric monitoring may also be used in a passive call monitoring mode, wherein periodic samples of the caller""s voice are provided to the CCUxe2x80x94and checked against a list of authorized voice printsxe2x80x94to ensure that no unauthorized callers are participating in a call, and to ensure that inmates are not sharing or selling relatively liberal calling privileges associated with a particular PIN or inmate account to other inmates that are subject to more limited calling privileges. The use of biometric voice verification (or xe2x80x9cvoice printsxe2x80x9d) can prevent PIN abuse in general. For example, if a particular inmate with restricted calling privileges, or no available funds, attempted to force (e.g., by threatening physical attack) another inmate with relatively non-restricted calling privileges (or available funds) to turn over his PIN, biometric voice verification would obviate this problem, as the voice would be used to validate entry into any inmate account.
The principal feature of the present invention is the implementation of a way to detect inmate or other regulated caller telephone calls to called parties, whereby said called parties act to bridge the inmate or regulated caller to some third party. Whereas regulated callers, by definition herein, are only permitted to communicate with certain called parties, the authority in charge of the caller or inmate""s calls are afforded the ability of preventing called parties from bridging telephone calls from inmates or other regulated parties to unauthorized or unknown third parties. Said authority has, at its option, the ability to prevent, terminate and/or track or monitor any of said attempts.
Broadly, the present invention takes the form of an apparatus and method for detecting and identifying disparate preselected signal sequences of spaced tone bursts. Such spaced tone bursts or tone signals may be originated by the called party in a called party""s effort toward bridging the caller or inmate with a third party. Such tones are the tones often generated during such bridging attempts, such as the ringing of the third party""s telephone, a busy signal during the attempted calling of a third party by the called party, a dial tone as the called party is dialing the number of the third party, SIT tones generated when the called party attempts a telephone call to a third party whose number has been, for example, disconnected, other call progress tones, such as those associated with telephone credit card usage, other DTMF tones, for example, those used by the third party to call the third party in the first place, and any other tones, thus obviating the need for any detection of hook flashes or other clicks and/or pops on the telephone line, that may unreliably be associated with attempts by called parties to place telephone calls to third parties.
In some further specific aspects of the invention, logic circuitry comprises gates and registers. The latter is used to store durations of tone bursts and spaces which the gates compare for consistencies with a preselected signal sequence. Further gates are utilized to detect one of a plurality of preselected error conditions. Occurrence of an error condition is used to override indication of a valid signal sequence and to identify possible malfunctions in apparatus used to generate the preselected signal sequences. The storage of certain tones may be desired, for example, with ring or busy signals. As those tones are often associated with specific cadences (ring ⅔ on, ⅓ off, and busy 50% on, 50% off), the sensing of cadence in addition to tone frequency can improve system reliability. The detection of tones can be accomplished by certain integrated circuits, such as the Teltone brand series of chips, designed to detect and digitally decode DTMF and/or SIT tones. Typically, DTMF tones are the 12 conventional Touch Tones (1-9, 0, # and ★), and SIT tones are generated by the local central office equipment when a call does not go through, for example, if a number is blocked from a particular telephone number, a number is no longer in use, a number has been disconnected, an area code has been changed, etc. With the present invention, such tones (DTMF or SIT), or other tones (dial, ringing, busy or call progress tones) are used to signal an inmate or other regulated telephone system that a called party (a party called by, e.g., an inmate) is attempting to bridge that telephone call together with some unknown and/or unauthorized third party. Upon the detection of such a tone (call progress tone or other tone), the present invention may either terminate the call between the inmate and the called party, or may evaluate what third party was called, to attempt to validate such a third party call.
Also, with the present invention, the third party call attempt may be stored, for present or future review by an institutional authority, and patterns may be monitored, so that prison officials may consider curtailing future inmate calls to particular called parties. Thus, third party call attempts can be tracked, both on a per inmate and on a per called party basis.
Thus, if inmates A through G all know to call a certain called party X so that called party X can bridge them to their respective unauthorized third parties, then, the prison officials will know that future calls to party X are to be blocked, regardless of who is initiating such a call, because called party X is suspected of being an individual who facilitates unauthorized third parties. Importantly, certain called parties may even attempt to bridge a call from one inmate to another call from another inmate. In that instance, keeping track of such attempts, and terminating such calls, is particularly important, as inmates within the same institution may be conspiring to do crime, such as breaking out of prison.
The present invention relies on some of the same circuitry used by certain customer owned coin operated telephones (COCOTS) and other facility based PBX equipment. Some such pay telephone stations are provided with apparatus for detecting when a called party has answered a call (initiated at the coin telephone station) by tracking call progress tones, and sensing tone cadence. The apparatus of the present invention may also include circuitry for inhibiting the indication of called party answer when a sequence of three predetermined (such as SIT) tones are received; such tones generally precede an intercept message such as one that announces that a telephone number has been changed or disconnected. The apparatus further includes circuitry for inhibiting the indication of called party answer when call progress tones are detected. Finally, the present invention can sense DTMF tones themselves, often used in the completion of calls by Touch Tone telephones.
The present invention thus obviates the need to rely on sensing clicks or pops associated with attempts by called parties to bridge calls via conference call circuitry or call waiting. Such reliance is disadvantageous. First, depending upon the local exchange carrier switch, call waiting and call conferencing, as provided by the telephone companies, may not even generate any click or pop (or other suitable pulse that could activate the Kitchin circuitry). Also, the circuitry of Kitchin is susceptible to false triggering, as it senses impulses that can occur randomly. To the contrary, applicant contends that the invention set forth herein is simpler and more accurate, certainly insofar as false triggering is concerned. Applicant contends that the sensing of tones exclusively as a means to restrict third party calls will lead to far less false triggering as compared to the Kitchin proposal. As applicant""s invention is not directed to sensing third party call attempts that do not involve tones, applicant senses only tonesxe2x80x94not impulses associated with hook flashes, as Kitchin requires. To the contrary, applicant contends that the present invention obviates the need for that by sensing other criteria that may be indicative of an attempt by a called party to bridge one telephone caller with another.